Export site measurement data to file

The following code exmple shows how you can query all the electricity measurements at a site for given time period, and store those measurements to a local .csv file. In this particular example we store all the energy measurements at the specified site measured in a 1 day period with a 10 minute aggregation level.

JavaScript

import fs from 'fs'
import axios from 'axios'
import csvWriter from 'csv-write-stream'

storeSiteElectricityMeasurements(
  '<INSERT_API_KEY>',
  '<INSERT_SITE_ID>',
  'energy',
  '2023-10-01',
  '2023-10-08',
  '1d',
  'energy_data_export.csv'
).then(() => console.log('completed'))

const storeSiteElectricityMeasurements = async(
  apiKey,
  siteId,
  type,
  from,
  to,
  aggregation,
  filename,
) => {
  let nextUrl = `https://api.sensorfact.nl/v1/sites/${siteId}/electricity/measurements/assets?from=${from}&to=${to}&measurement_type=${type}&aggregation=${aggregation}`

  while (nextUrl) {
    const response = await axios.get(nextUrl, {headers: {'x-api-key': apiKey}})
    const { data } = response.data

    await writeMeasurements(type, data, filename)
    nextUrl = response.data.paging?.next ?? null
  }
}

const writeMeasurements = async(type, assets, filename) => {
  const writer = !fs.existsSync(filename) 
    ? csvWriter({ headers: ['asset_id', 'type', 'unit', 'timestamp', 'value']}) 
    : csvWriter({sendHeaders: false});

  writer.pipe(fs.createWriteStream(file, {flags: 'a'}))
  
  const rows = assets.flatMap(asset => asset.measurements.map(measurement => ({
    asset_id: asset.id,
    type,
    unit: asset.unit,
    timestamp: measurement.time,
    value: measurement.value
  })))

  for (const row of rows) {
    writer.write(row)
  }

  writer.end()
}

Python

import requests
import csv

key = "<INSERT_YOUR_API_KEY_HERE>"
site_id = "<INSERT_YOUR_SITE_ID_HERE>"
from_date = "2023-10-01"
to_date = "2023-10-08"
aggregation = "1d"
measurement_type = "energy"

next_url = f"https://api.sensorfact.nl/v1/sites/{site_id}/electricity/measurements/assets?from={from_date}&to={to_date}&measurement_type={measurement_type}&aggregation={aggregation}"
rows=[]

while next_url:
    r=requests.get(next_url, headers={"x-api-key":key})

    response = r.json()
    assets = response["data"]

    for asset in assets:
        print(asset["name"])
        for measurement in asset["measurements"]:
            row={
                "time": measurement["time"],
                "asset_id": asset["id"],
                "asset_name": asset["name"],
                "unit": asset["unit"],
                "value": measurement["value"]
            }
            rows.append(row)
    if ("paging" in response):
        next_url = response["paging"]["next"]
    else:
        next_url = None

# csv field names 
fields = ["time", "asset_id", "asset_name", "unit", "value"] 

with open("export.csv", "w", newline="") as file:
    writer = csv.DictWriter(file, fieldnames = fields)
    writer.writeheader() 
    writer.writerows(rows)

print("done")